2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
18 #include <linux/sched.h>
19 #include <linux/bio.h>
20 #include <linux/slab.h>
21 #include <linux/buffer_head.h>
22 #include <linux/blkdev.h>
23 #include <linux/random.h>
24 #include <linux/iocontext.h>
25 #include <linux/capability.h>
26 #include <asm/div64.h>
29 #include "extent_map.h"
31 #include "transaction.h"
32 #include "print-tree.h"
34 #include "async-thread.h"
36 static int init_first_rw_device(struct btrfs_trans_handle *trans,
37 struct btrfs_root *root,
38 struct btrfs_device *device);
39 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
41 static DEFINE_MUTEX(uuid_mutex);
42 static LIST_HEAD(fs_uuids);
44 static void lock_chunks(struct btrfs_root *root)
46 mutex_lock(&root->fs_info->chunk_mutex);
49 static void unlock_chunks(struct btrfs_root *root)
51 mutex_unlock(&root->fs_info->chunk_mutex);
54 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
56 struct btrfs_device *device;
57 WARN_ON(fs_devices->opened);
58 while (!list_empty(&fs_devices->devices)) {
59 device = list_entry(fs_devices->devices.next,
60 struct btrfs_device, dev_list);
61 list_del(&device->dev_list);
68 int btrfs_cleanup_fs_uuids(void)
70 struct btrfs_fs_devices *fs_devices;
72 while (!list_empty(&fs_uuids)) {
73 fs_devices = list_entry(fs_uuids.next,
74 struct btrfs_fs_devices, list);
75 list_del(&fs_devices->list);
76 free_fs_devices(fs_devices);
81 static noinline struct btrfs_device *__find_device(struct list_head *head,
84 struct btrfs_device *dev;
86 list_for_each_entry(dev, head, dev_list) {
87 if (dev->devid == devid &&
88 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
95 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
97 struct btrfs_fs_devices *fs_devices;
99 list_for_each_entry(fs_devices, &fs_uuids, list) {
100 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
106 static void requeue_list(struct btrfs_pending_bios *pending_bios,
107 struct bio *head, struct bio *tail)
110 struct bio *old_head;
112 old_head = pending_bios->head;
113 pending_bios->head = head;
114 if (pending_bios->tail)
115 tail->bi_next = old_head;
117 pending_bios->tail = tail;
121 * we try to collect pending bios for a device so we don't get a large
122 * number of procs sending bios down to the same device. This greatly
123 * improves the schedulers ability to collect and merge the bios.
125 * But, it also turns into a long list of bios to process and that is sure
126 * to eventually make the worker thread block. The solution here is to
127 * make some progress and then put this work struct back at the end of
128 * the list if the block device is congested. This way, multiple devices
129 * can make progress from a single worker thread.
131 static noinline int run_scheduled_bios(struct btrfs_device *device)
134 struct backing_dev_info *bdi;
135 struct btrfs_fs_info *fs_info;
136 struct btrfs_pending_bios *pending_bios;
140 unsigned long num_run;
141 unsigned long batch_run = 0;
143 unsigned long last_waited = 0;
145 int sync_pending = 0;
146 struct blk_plug plug;
149 * this function runs all the bios we've collected for
150 * a particular device. We don't want to wander off to
151 * another device without first sending all of these down.
152 * So, setup a plug here and finish it off before we return
154 blk_start_plug(&plug);
156 bdi = blk_get_backing_dev_info(device->bdev);
157 fs_info = device->dev_root->fs_info;
158 limit = btrfs_async_submit_limit(fs_info);
159 limit = limit * 2 / 3;
162 spin_lock(&device->io_lock);
167 /* take all the bios off the list at once and process them
168 * later on (without the lock held). But, remember the
169 * tail and other pointers so the bios can be properly reinserted
170 * into the list if we hit congestion
172 if (!force_reg && device->pending_sync_bios.head) {
173 pending_bios = &device->pending_sync_bios;
176 pending_bios = &device->pending_bios;
180 pending = pending_bios->head;
181 tail = pending_bios->tail;
182 WARN_ON(pending && !tail);
185 * if pending was null this time around, no bios need processing
186 * at all and we can stop. Otherwise it'll loop back up again
187 * and do an additional check so no bios are missed.
189 * device->running_pending is used to synchronize with the
192 if (device->pending_sync_bios.head == NULL &&
193 device->pending_bios.head == NULL) {
195 device->running_pending = 0;
198 device->running_pending = 1;
201 pending_bios->head = NULL;
202 pending_bios->tail = NULL;
204 spin_unlock(&device->io_lock);
209 /* we want to work on both lists, but do more bios on the
210 * sync list than the regular list
213 pending_bios != &device->pending_sync_bios &&
214 device->pending_sync_bios.head) ||
215 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
216 device->pending_bios.head)) {
217 spin_lock(&device->io_lock);
218 requeue_list(pending_bios, pending, tail);
223 pending = pending->bi_next;
225 atomic_dec(&fs_info->nr_async_bios);
227 if (atomic_read(&fs_info->nr_async_bios) < limit &&
228 waitqueue_active(&fs_info->async_submit_wait))
229 wake_up(&fs_info->async_submit_wait);
231 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
234 * if we're doing the sync list, record that our
235 * plug has some sync requests on it
237 * If we're doing the regular list and there are
238 * sync requests sitting around, unplug before
241 if (pending_bios == &device->pending_sync_bios) {
243 } else if (sync_pending) {
244 blk_finish_plug(&plug);
245 blk_start_plug(&plug);
249 submit_bio(cur->bi_rw, cur);
256 * we made progress, there is more work to do and the bdi
257 * is now congested. Back off and let other work structs
260 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
261 fs_info->fs_devices->open_devices > 1) {
262 struct io_context *ioc;
264 ioc = current->io_context;
267 * the main goal here is that we don't want to
268 * block if we're going to be able to submit
269 * more requests without blocking.
271 * This code does two great things, it pokes into
272 * the elevator code from a filesystem _and_
273 * it makes assumptions about how batching works.
275 if (ioc && ioc->nr_batch_requests > 0 &&
276 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
278 ioc->last_waited == last_waited)) {
280 * we want to go through our batch of
281 * requests and stop. So, we copy out
282 * the ioc->last_waited time and test
283 * against it before looping
285 last_waited = ioc->last_waited;
290 spin_lock(&device->io_lock);
291 requeue_list(pending_bios, pending, tail);
292 device->running_pending = 1;
294 spin_unlock(&device->io_lock);
295 btrfs_requeue_work(&device->work);
298 /* unplug every 64 requests just for good measure */
299 if (batch_run % 64 == 0) {
300 blk_finish_plug(&plug);
301 blk_start_plug(&plug);
310 spin_lock(&device->io_lock);
311 if (device->pending_bios.head || device->pending_sync_bios.head)
313 spin_unlock(&device->io_lock);
316 blk_finish_plug(&plug);
320 static void pending_bios_fn(struct btrfs_work *work)
322 struct btrfs_device *device;
324 device = container_of(work, struct btrfs_device, work);
325 run_scheduled_bios(device);
328 static noinline int device_list_add(const char *path,
329 struct btrfs_super_block *disk_super,
330 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
332 struct btrfs_device *device;
333 struct btrfs_fs_devices *fs_devices;
334 u64 found_transid = btrfs_super_generation(disk_super);
337 fs_devices = find_fsid(disk_super->fsid);
339 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
342 INIT_LIST_HEAD(&fs_devices->devices);
343 INIT_LIST_HEAD(&fs_devices->alloc_list);
344 list_add(&fs_devices->list, &fs_uuids);
345 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
346 fs_devices->latest_devid = devid;
347 fs_devices->latest_trans = found_transid;
348 mutex_init(&fs_devices->device_list_mutex);
351 device = __find_device(&fs_devices->devices, devid,
352 disk_super->dev_item.uuid);
355 if (fs_devices->opened)
358 device = kzalloc(sizeof(*device), GFP_NOFS);
360 /* we can safely leave the fs_devices entry around */
363 device->devid = devid;
364 device->work.func = pending_bios_fn;
365 memcpy(device->uuid, disk_super->dev_item.uuid,
367 spin_lock_init(&device->io_lock);
368 device->name = kstrdup(path, GFP_NOFS);
373 INIT_LIST_HEAD(&device->dev_alloc_list);
375 /* init readahead state */
376 spin_lock_init(&device->reada_lock);
377 device->reada_curr_zone = NULL;
378 atomic_set(&device->reada_in_flight, 0);
379 device->reada_next = 0;
380 INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT);
381 INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT);
383 mutex_lock(&fs_devices->device_list_mutex);
384 list_add_rcu(&device->dev_list, &fs_devices->devices);
385 mutex_unlock(&fs_devices->device_list_mutex);
387 device->fs_devices = fs_devices;
388 fs_devices->num_devices++;
389 } else if (!device->name || strcmp(device->name, path)) {
390 name = kstrdup(path, GFP_NOFS);
395 if (device->missing) {
396 fs_devices->missing_devices--;
401 if (found_transid > fs_devices->latest_trans) {
402 fs_devices->latest_devid = devid;
403 fs_devices->latest_trans = found_transid;
405 *fs_devices_ret = fs_devices;
409 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
411 struct btrfs_fs_devices *fs_devices;
412 struct btrfs_device *device;
413 struct btrfs_device *orig_dev;
415 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
417 return ERR_PTR(-ENOMEM);
419 INIT_LIST_HEAD(&fs_devices->devices);
420 INIT_LIST_HEAD(&fs_devices->alloc_list);
421 INIT_LIST_HEAD(&fs_devices->list);
422 mutex_init(&fs_devices->device_list_mutex);
423 fs_devices->latest_devid = orig->latest_devid;
424 fs_devices->latest_trans = orig->latest_trans;
425 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid));
427 /* We have held the volume lock, it is safe to get the devices. */
428 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
429 device = kzalloc(sizeof(*device), GFP_NOFS);
433 device->name = kstrdup(orig_dev->name, GFP_NOFS);
439 device->devid = orig_dev->devid;
440 device->work.func = pending_bios_fn;
441 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid));
442 spin_lock_init(&device->io_lock);
443 INIT_LIST_HEAD(&device->dev_list);
444 INIT_LIST_HEAD(&device->dev_alloc_list);
446 list_add(&device->dev_list, &fs_devices->devices);
447 device->fs_devices = fs_devices;
448 fs_devices->num_devices++;
452 free_fs_devices(fs_devices);
453 return ERR_PTR(-ENOMEM);
456 int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
458 struct btrfs_device *device, *next;
460 mutex_lock(&uuid_mutex);
462 /* This is the initialized path, it is safe to release the devices. */
463 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
464 if (device->in_fs_metadata)
468 blkdev_put(device->bdev, device->mode);
470 fs_devices->open_devices--;
472 if (device->writeable) {
473 list_del_init(&device->dev_alloc_list);
474 device->writeable = 0;
475 fs_devices->rw_devices--;
477 list_del_init(&device->dev_list);
478 fs_devices->num_devices--;
483 if (fs_devices->seed) {
484 fs_devices = fs_devices->seed;
488 mutex_unlock(&uuid_mutex);
492 static void __free_device(struct work_struct *work)
494 struct btrfs_device *device;
496 device = container_of(work, struct btrfs_device, rcu_work);
499 blkdev_put(device->bdev, device->mode);
505 static void free_device(struct rcu_head *head)
507 struct btrfs_device *device;
509 device = container_of(head, struct btrfs_device, rcu);
511 INIT_WORK(&device->rcu_work, __free_device);
512 schedule_work(&device->rcu_work);
515 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
517 struct btrfs_device *device;
519 if (--fs_devices->opened > 0)
522 mutex_lock(&fs_devices->device_list_mutex);
523 list_for_each_entry(device, &fs_devices->devices, dev_list) {
524 struct btrfs_device *new_device;
527 fs_devices->open_devices--;
529 if (device->writeable) {
530 list_del_init(&device->dev_alloc_list);
531 fs_devices->rw_devices--;
534 if (device->can_discard)
535 fs_devices->num_can_discard--;
537 new_device = kmalloc(sizeof(*new_device), GFP_NOFS);
539 memcpy(new_device, device, sizeof(*new_device));
540 new_device->name = kstrdup(device->name, GFP_NOFS);
541 BUG_ON(device->name && !new_device->name);
542 new_device->bdev = NULL;
543 new_device->writeable = 0;
544 new_device->in_fs_metadata = 0;
545 new_device->can_discard = 0;
546 list_replace_rcu(&device->dev_list, &new_device->dev_list);
548 call_rcu(&device->rcu, free_device);
550 mutex_unlock(&fs_devices->device_list_mutex);
552 WARN_ON(fs_devices->open_devices);
553 WARN_ON(fs_devices->rw_devices);
554 fs_devices->opened = 0;
555 fs_devices->seeding = 0;
560 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
562 struct btrfs_fs_devices *seed_devices = NULL;
565 mutex_lock(&uuid_mutex);
566 ret = __btrfs_close_devices(fs_devices);
567 if (!fs_devices->opened) {
568 seed_devices = fs_devices->seed;
569 fs_devices->seed = NULL;
571 mutex_unlock(&uuid_mutex);
573 while (seed_devices) {
574 fs_devices = seed_devices;
575 seed_devices = fs_devices->seed;
576 __btrfs_close_devices(fs_devices);
577 free_fs_devices(fs_devices);
582 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
583 fmode_t flags, void *holder)
585 struct request_queue *q;
586 struct block_device *bdev;
587 struct list_head *head = &fs_devices->devices;
588 struct btrfs_device *device;
589 struct block_device *latest_bdev = NULL;
590 struct buffer_head *bh;
591 struct btrfs_super_block *disk_super;
592 u64 latest_devid = 0;
593 u64 latest_transid = 0;
600 list_for_each_entry(device, head, dev_list) {
606 bdev = blkdev_get_by_path(device->name, flags, holder);
608 printk(KERN_INFO "open %s failed\n", device->name);
611 set_blocksize(bdev, 4096);
613 bh = btrfs_read_dev_super(bdev);
617 disk_super = (struct btrfs_super_block *)bh->b_data;
618 devid = btrfs_stack_device_id(&disk_super->dev_item);
619 if (devid != device->devid)
622 if (memcmp(device->uuid, disk_super->dev_item.uuid,
626 device->generation = btrfs_super_generation(disk_super);
627 if (!latest_transid || device->generation > latest_transid) {
628 latest_devid = devid;
629 latest_transid = device->generation;
633 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
634 device->writeable = 0;
636 device->writeable = !bdev_read_only(bdev);
640 q = bdev_get_queue(bdev);
641 if (blk_queue_discard(q)) {
642 device->can_discard = 1;
643 fs_devices->num_can_discard++;
647 device->in_fs_metadata = 0;
648 device->mode = flags;
650 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
651 fs_devices->rotating = 1;
653 fs_devices->open_devices++;
654 if (device->writeable) {
655 fs_devices->rw_devices++;
656 list_add(&device->dev_alloc_list,
657 &fs_devices->alloc_list);
665 blkdev_put(bdev, flags);
669 if (fs_devices->open_devices == 0) {
673 fs_devices->seeding = seeding;
674 fs_devices->opened = 1;
675 fs_devices->latest_bdev = latest_bdev;
676 fs_devices->latest_devid = latest_devid;
677 fs_devices->latest_trans = latest_transid;
678 fs_devices->total_rw_bytes = 0;
683 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
684 fmode_t flags, void *holder)
688 mutex_lock(&uuid_mutex);
689 if (fs_devices->opened) {
690 fs_devices->opened++;
693 ret = __btrfs_open_devices(fs_devices, flags, holder);
695 mutex_unlock(&uuid_mutex);
699 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
700 struct btrfs_fs_devices **fs_devices_ret)
702 struct btrfs_super_block *disk_super;
703 struct block_device *bdev;
704 struct buffer_head *bh;
709 mutex_lock(&uuid_mutex);
712 bdev = blkdev_get_by_path(path, flags, holder);
719 ret = set_blocksize(bdev, 4096);
722 bh = btrfs_read_dev_super(bdev);
727 disk_super = (struct btrfs_super_block *)bh->b_data;
728 devid = btrfs_stack_device_id(&disk_super->dev_item);
729 transid = btrfs_super_generation(disk_super);
730 if (disk_super->label[0])
731 printk(KERN_INFO "device label %s ", disk_super->label);
733 printk(KERN_INFO "device fsid %pU ", disk_super->fsid);
734 printk(KERN_CONT "devid %llu transid %llu %s\n",
735 (unsigned long long)devid, (unsigned long long)transid, path);
736 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
740 blkdev_put(bdev, flags);
742 mutex_unlock(&uuid_mutex);
746 /* helper to account the used device space in the range */
747 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
748 u64 end, u64 *length)
750 struct btrfs_key key;
751 struct btrfs_root *root = device->dev_root;
752 struct btrfs_dev_extent *dev_extent;
753 struct btrfs_path *path;
757 struct extent_buffer *l;
761 if (start >= device->total_bytes)
764 path = btrfs_alloc_path();
769 key.objectid = device->devid;
771 key.type = BTRFS_DEV_EXTENT_KEY;
773 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
777 ret = btrfs_previous_item(root, path, key.objectid, key.type);
784 slot = path->slots[0];
785 if (slot >= btrfs_header_nritems(l)) {
786 ret = btrfs_next_leaf(root, path);
794 btrfs_item_key_to_cpu(l, &key, slot);
796 if (key.objectid < device->devid)
799 if (key.objectid > device->devid)
802 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
805 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
806 extent_end = key.offset + btrfs_dev_extent_length(l,
808 if (key.offset <= start && extent_end > end) {
809 *length = end - start + 1;
811 } else if (key.offset <= start && extent_end > start)
812 *length += extent_end - start;
813 else if (key.offset > start && extent_end <= end)
814 *length += extent_end - key.offset;
815 else if (key.offset > start && key.offset <= end) {
816 *length += end - key.offset + 1;
818 } else if (key.offset > end)
826 btrfs_free_path(path);
831 * find_free_dev_extent - find free space in the specified device
832 * @device: the device which we search the free space in
833 * @num_bytes: the size of the free space that we need
834 * @start: store the start of the free space.
835 * @len: the size of the free space. that we find, or the size of the max
836 * free space if we don't find suitable free space
838 * this uses a pretty simple search, the expectation is that it is
839 * called very infrequently and that a given device has a small number
842 * @start is used to store the start of the free space if we find. But if we
843 * don't find suitable free space, it will be used to store the start position
844 * of the max free space.
846 * @len is used to store the size of the free space that we find.
847 * But if we don't find suitable free space, it is used to store the size of
848 * the max free space.
850 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
851 u64 *start, u64 *len)
853 struct btrfs_key key;
854 struct btrfs_root *root = device->dev_root;
855 struct btrfs_dev_extent *dev_extent;
856 struct btrfs_path *path;
862 u64 search_end = device->total_bytes;
865 struct extent_buffer *l;
867 /* FIXME use last free of some kind */
869 /* we don't want to overwrite the superblock on the drive,
870 * so we make sure to start at an offset of at least 1MB
872 search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
874 max_hole_start = search_start;
878 if (search_start >= search_end) {
883 path = btrfs_alloc_path();
890 key.objectid = device->devid;
891 key.offset = search_start;
892 key.type = BTRFS_DEV_EXTENT_KEY;
894 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
898 ret = btrfs_previous_item(root, path, key.objectid, key.type);
905 slot = path->slots[0];
906 if (slot >= btrfs_header_nritems(l)) {
907 ret = btrfs_next_leaf(root, path);
915 btrfs_item_key_to_cpu(l, &key, slot);
917 if (key.objectid < device->devid)
920 if (key.objectid > device->devid)
923 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
926 if (key.offset > search_start) {
927 hole_size = key.offset - search_start;
929 if (hole_size > max_hole_size) {
930 max_hole_start = search_start;
931 max_hole_size = hole_size;
935 * If this free space is greater than which we need,
936 * it must be the max free space that we have found
937 * until now, so max_hole_start must point to the start
938 * of this free space and the length of this free space
939 * is stored in max_hole_size. Thus, we return
940 * max_hole_start and max_hole_size and go back to the
943 if (hole_size >= num_bytes) {
949 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
950 extent_end = key.offset + btrfs_dev_extent_length(l,
952 if (extent_end > search_start)
953 search_start = extent_end;
960 * At this point, search_start should be the end of
961 * allocated dev extents, and when shrinking the device,
962 * search_end may be smaller than search_start.
964 if (search_end > search_start)
965 hole_size = search_end - search_start;
967 if (hole_size > max_hole_size) {
968 max_hole_start = search_start;
969 max_hole_size = hole_size;
973 if (hole_size < num_bytes)
979 btrfs_free_path(path);
981 *start = max_hole_start;
983 *len = max_hole_size;
987 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
988 struct btrfs_device *device,
992 struct btrfs_path *path;
993 struct btrfs_root *root = device->dev_root;
994 struct btrfs_key key;
995 struct btrfs_key found_key;
996 struct extent_buffer *leaf = NULL;
997 struct btrfs_dev_extent *extent = NULL;
999 path = btrfs_alloc_path();
1003 key.objectid = device->devid;
1005 key.type = BTRFS_DEV_EXTENT_KEY;
1007 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1009 ret = btrfs_previous_item(root, path, key.objectid,
1010 BTRFS_DEV_EXTENT_KEY);
1013 leaf = path->nodes[0];
1014 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1015 extent = btrfs_item_ptr(leaf, path->slots[0],
1016 struct btrfs_dev_extent);
1017 BUG_ON(found_key.offset > start || found_key.offset +
1018 btrfs_dev_extent_length(leaf, extent) < start);
1020 btrfs_release_path(path);
1022 } else if (ret == 0) {
1023 leaf = path->nodes[0];
1024 extent = btrfs_item_ptr(leaf, path->slots[0],
1025 struct btrfs_dev_extent);
1029 if (device->bytes_used > 0) {
1030 u64 len = btrfs_dev_extent_length(leaf, extent);
1031 device->bytes_used -= len;
1032 spin_lock(&root->fs_info->free_chunk_lock);
1033 root->fs_info->free_chunk_space += len;
1034 spin_unlock(&root->fs_info->free_chunk_lock);
1036 ret = btrfs_del_item(trans, root, path);
1039 btrfs_free_path(path);
1043 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1044 struct btrfs_device *device,
1045 u64 chunk_tree, u64 chunk_objectid,
1046 u64 chunk_offset, u64 start, u64 num_bytes)
1049 struct btrfs_path *path;
1050 struct btrfs_root *root = device->dev_root;
1051 struct btrfs_dev_extent *extent;
1052 struct extent_buffer *leaf;
1053 struct btrfs_key key;
1055 WARN_ON(!device->in_fs_metadata);
1056 path = btrfs_alloc_path();
1060 key.objectid = device->devid;
1062 key.type = BTRFS_DEV_EXTENT_KEY;
1063 ret = btrfs_insert_empty_item(trans, root, path, &key,
1067 leaf = path->nodes[0];
1068 extent = btrfs_item_ptr(leaf, path->slots[0],
1069 struct btrfs_dev_extent);
1070 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1071 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1072 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1074 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1075 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent),
1078 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1079 btrfs_mark_buffer_dirty(leaf);
1080 btrfs_free_path(path);
1084 static noinline int find_next_chunk(struct btrfs_root *root,
1085 u64 objectid, u64 *offset)
1087 struct btrfs_path *path;
1089 struct btrfs_key key;
1090 struct btrfs_chunk *chunk;
1091 struct btrfs_key found_key;
1093 path = btrfs_alloc_path();
1097 key.objectid = objectid;
1098 key.offset = (u64)-1;
1099 key.type = BTRFS_CHUNK_ITEM_KEY;
1101 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1107 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY);
1111 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1113 if (found_key.objectid != objectid)
1116 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
1117 struct btrfs_chunk);
1118 *offset = found_key.offset +
1119 btrfs_chunk_length(path->nodes[0], chunk);
1124 btrfs_free_path(path);
1128 static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid)
1131 struct btrfs_key key;
1132 struct btrfs_key found_key;
1133 struct btrfs_path *path;
1135 root = root->fs_info->chunk_root;
1137 path = btrfs_alloc_path();
1141 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1142 key.type = BTRFS_DEV_ITEM_KEY;
1143 key.offset = (u64)-1;
1145 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1151 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID,
1152 BTRFS_DEV_ITEM_KEY);
1156 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1158 *objectid = found_key.offset + 1;
1162 btrfs_free_path(path);
1167 * the device information is stored in the chunk root
1168 * the btrfs_device struct should be fully filled in
1170 int btrfs_add_device(struct btrfs_trans_handle *trans,
1171 struct btrfs_root *root,
1172 struct btrfs_device *device)
1175 struct btrfs_path *path;
1176 struct btrfs_dev_item *dev_item;
1177 struct extent_buffer *leaf;
1178 struct btrfs_key key;
1181 root = root->fs_info->chunk_root;
1183 path = btrfs_alloc_path();
1187 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1188 key.type = BTRFS_DEV_ITEM_KEY;
1189 key.offset = device->devid;
1191 ret = btrfs_insert_empty_item(trans, root, path, &key,
1196 leaf = path->nodes[0];
1197 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1199 btrfs_set_device_id(leaf, dev_item, device->devid);
1200 btrfs_set_device_generation(leaf, dev_item, 0);
1201 btrfs_set_device_type(leaf, dev_item, device->type);
1202 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1203 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1204 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1205 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
1206 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
1207 btrfs_set_device_group(leaf, dev_item, 0);
1208 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1209 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1210 btrfs_set_device_start_offset(leaf, dev_item, 0);
1212 ptr = (unsigned long)btrfs_device_uuid(dev_item);
1213 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1214 ptr = (unsigned long)btrfs_device_fsid(dev_item);
1215 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1216 btrfs_mark_buffer_dirty(leaf);
1220 btrfs_free_path(path);
1224 static int btrfs_rm_dev_item(struct btrfs_root *root,
1225 struct btrfs_device *device)
1228 struct btrfs_path *path;
1229 struct btrfs_key key;
1230 struct btrfs_trans_handle *trans;
1232 root = root->fs_info->chunk_root;
1234 path = btrfs_alloc_path();
1238 trans = btrfs_start_transaction(root, 0);
1239 if (IS_ERR(trans)) {
1240 btrfs_free_path(path);
1241 return PTR_ERR(trans);
1243 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1244 key.type = BTRFS_DEV_ITEM_KEY;
1245 key.offset = device->devid;
1248 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1257 ret = btrfs_del_item(trans, root, path);
1261 btrfs_free_path(path);
1262 unlock_chunks(root);
1263 btrfs_commit_transaction(trans, root);
1267 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1269 struct btrfs_device *device;
1270 struct btrfs_device *next_device;
1271 struct block_device *bdev;
1272 struct buffer_head *bh = NULL;
1273 struct btrfs_super_block *disk_super;
1274 struct btrfs_fs_devices *cur_devices;
1280 bool clear_super = false;
1282 mutex_lock(&uuid_mutex);
1283 mutex_lock(&root->fs_info->volume_mutex);
1285 all_avail = root->fs_info->avail_data_alloc_bits |
1286 root->fs_info->avail_system_alloc_bits |
1287 root->fs_info->avail_metadata_alloc_bits;
1289 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) &&
1290 root->fs_info->fs_devices->num_devices <= 4) {
1291 printk(KERN_ERR "btrfs: unable to go below four devices "
1297 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) &&
1298 root->fs_info->fs_devices->num_devices <= 2) {
1299 printk(KERN_ERR "btrfs: unable to go below two "
1300 "devices on raid1\n");
1305 if (strcmp(device_path, "missing") == 0) {
1306 struct list_head *devices;
1307 struct btrfs_device *tmp;
1310 devices = &root->fs_info->fs_devices->devices;
1312 * It is safe to read the devices since the volume_mutex
1315 list_for_each_entry(tmp, devices, dev_list) {
1316 if (tmp->in_fs_metadata && !tmp->bdev) {
1325 printk(KERN_ERR "btrfs: no missing devices found to "
1330 bdev = blkdev_get_by_path(device_path, FMODE_READ | FMODE_EXCL,
1331 root->fs_info->bdev_holder);
1333 ret = PTR_ERR(bdev);
1337 set_blocksize(bdev, 4096);
1338 bh = btrfs_read_dev_super(bdev);
1343 disk_super = (struct btrfs_super_block *)bh->b_data;
1344 devid = btrfs_stack_device_id(&disk_super->dev_item);
1345 dev_uuid = disk_super->dev_item.uuid;
1346 device = btrfs_find_device(root, devid, dev_uuid,
1354 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1355 printk(KERN_ERR "btrfs: unable to remove the only writeable "
1361 if (device->writeable) {
1363 list_del_init(&device->dev_alloc_list);
1364 unlock_chunks(root);
1365 root->fs_info->fs_devices->rw_devices--;
1369 ret = btrfs_shrink_device(device, 0);
1373 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1377 spin_lock(&root->fs_info->free_chunk_lock);
1378 root->fs_info->free_chunk_space = device->total_bytes -
1380 spin_unlock(&root->fs_info->free_chunk_lock);
1382 device->in_fs_metadata = 0;
1383 btrfs_scrub_cancel_dev(root, device);
1386 * the device list mutex makes sure that we don't change
1387 * the device list while someone else is writing out all
1388 * the device supers.
1391 cur_devices = device->fs_devices;
1392 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1393 list_del_rcu(&device->dev_list);
1395 device->fs_devices->num_devices--;
1397 if (device->missing)
1398 root->fs_info->fs_devices->missing_devices--;
1400 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1401 struct btrfs_device, dev_list);
1402 if (device->bdev == root->fs_info->sb->s_bdev)
1403 root->fs_info->sb->s_bdev = next_device->bdev;
1404 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1405 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1408 device->fs_devices->open_devices--;
1410 call_rcu(&device->rcu, free_device);
1411 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1413 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1414 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1416 if (cur_devices->open_devices == 0) {
1417 struct btrfs_fs_devices *fs_devices;
1418 fs_devices = root->fs_info->fs_devices;
1419 while (fs_devices) {
1420 if (fs_devices->seed == cur_devices)
1422 fs_devices = fs_devices->seed;
1424 fs_devices->seed = cur_devices->seed;
1425 cur_devices->seed = NULL;
1427 __btrfs_close_devices(cur_devices);
1428 unlock_chunks(root);
1429 free_fs_devices(cur_devices);
1433 * at this point, the device is zero sized. We want to
1434 * remove it from the devices list and zero out the old super
1437 /* make sure this device isn't detected as part of
1440 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1441 set_buffer_dirty(bh);
1442 sync_dirty_buffer(bh);
1451 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1453 mutex_unlock(&root->fs_info->volume_mutex);
1454 mutex_unlock(&uuid_mutex);
1457 if (device->writeable) {
1459 list_add(&device->dev_alloc_list,
1460 &root->fs_info->fs_devices->alloc_list);
1461 unlock_chunks(root);
1462 root->fs_info->fs_devices->rw_devices++;
1468 * does all the dirty work required for changing file system's UUID.
1470 static int btrfs_prepare_sprout(struct btrfs_root *root)
1472 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
1473 struct btrfs_fs_devices *old_devices;
1474 struct btrfs_fs_devices *seed_devices;
1475 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
1476 struct btrfs_device *device;
1479 BUG_ON(!mutex_is_locked(&uuid_mutex));
1480 if (!fs_devices->seeding)
1483 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
1487 old_devices = clone_fs_devices(fs_devices);
1488 if (IS_ERR(old_devices)) {
1489 kfree(seed_devices);
1490 return PTR_ERR(old_devices);
1493 list_add(&old_devices->list, &fs_uuids);
1495 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
1496 seed_devices->opened = 1;
1497 INIT_LIST_HEAD(&seed_devices->devices);
1498 INIT_LIST_HEAD(&seed_devices->alloc_list);
1499 mutex_init(&seed_devices->device_list_mutex);
1501 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1502 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
1504 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1506 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
1507 list_for_each_entry(device, &seed_devices->devices, dev_list) {
1508 device->fs_devices = seed_devices;
1511 fs_devices->seeding = 0;
1512 fs_devices->num_devices = 0;
1513 fs_devices->open_devices = 0;
1514 fs_devices->seed = seed_devices;
1516 generate_random_uuid(fs_devices->fsid);
1517 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1518 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1519 super_flags = btrfs_super_flags(disk_super) &
1520 ~BTRFS_SUPER_FLAG_SEEDING;
1521 btrfs_set_super_flags(disk_super, super_flags);
1527 * strore the expected generation for seed devices in device items.
1529 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
1530 struct btrfs_root *root)
1532 struct btrfs_path *path;
1533 struct extent_buffer *leaf;
1534 struct btrfs_dev_item *dev_item;
1535 struct btrfs_device *device;
1536 struct btrfs_key key;
1537 u8 fs_uuid[BTRFS_UUID_SIZE];
1538 u8 dev_uuid[BTRFS_UUID_SIZE];
1542 path = btrfs_alloc_path();
1546 root = root->fs_info->chunk_root;
1547 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1549 key.type = BTRFS_DEV_ITEM_KEY;
1552 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1556 leaf = path->nodes[0];
1558 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1559 ret = btrfs_next_leaf(root, path);
1564 leaf = path->nodes[0];
1565 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1566 btrfs_release_path(path);
1570 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1571 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
1572 key.type != BTRFS_DEV_ITEM_KEY)
1575 dev_item = btrfs_item_ptr(leaf, path->slots[0],
1576 struct btrfs_dev_item);
1577 devid = btrfs_device_id(leaf, dev_item);
1578 read_extent_buffer(leaf, dev_uuid,
1579 (unsigned long)btrfs_device_uuid(dev_item),
1581 read_extent_buffer(leaf, fs_uuid,
1582 (unsigned long)btrfs_device_fsid(dev_item),
1584 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
1587 if (device->fs_devices->seeding) {
1588 btrfs_set_device_generation(leaf, dev_item,
1589 device->generation);
1590 btrfs_mark_buffer_dirty(leaf);
1598 btrfs_free_path(path);
1602 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
1604 struct request_queue *q;
1605 struct btrfs_trans_handle *trans;
1606 struct btrfs_device *device;
1607 struct block_device *bdev;
1608 struct list_head *devices;
1609 struct super_block *sb = root->fs_info->sb;
1611 int seeding_dev = 0;
1614 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
1617 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
1618 root->fs_info->bdev_holder);
1620 return PTR_ERR(bdev);
1622 if (root->fs_info->fs_devices->seeding) {
1624 down_write(&sb->s_umount);
1625 mutex_lock(&uuid_mutex);
1628 filemap_write_and_wait(bdev->bd_inode->i_mapping);
1629 mutex_lock(&root->fs_info->volume_mutex);
1631 devices = &root->fs_info->fs_devices->devices;
1633 * we have the volume lock, so we don't need the extra
1634 * device list mutex while reading the list here.
1636 list_for_each_entry(device, devices, dev_list) {
1637 if (device->bdev == bdev) {
1643 device = kzalloc(sizeof(*device), GFP_NOFS);
1645 /* we can safely leave the fs_devices entry around */
1650 device->name = kstrdup(device_path, GFP_NOFS);
1651 if (!device->name) {
1657 ret = find_next_devid(root, &device->devid);
1659 kfree(device->name);
1664 trans = btrfs_start_transaction(root, 0);
1665 if (IS_ERR(trans)) {
1666 kfree(device->name);
1668 ret = PTR_ERR(trans);
1674 q = bdev_get_queue(bdev);
1675 if (blk_queue_discard(q))
1676 device->can_discard = 1;
1677 device->writeable = 1;
1678 device->work.func = pending_bios_fn;
1679 generate_random_uuid(device->uuid);
1680 spin_lock_init(&device->io_lock);
1681 device->generation = trans->transid;
1682 device->io_width = root->sectorsize;
1683 device->io_align = root->sectorsize;
1684 device->sector_size = root->sectorsize;
1685 device->total_bytes = i_size_read(bdev->bd_inode);
1686 device->disk_total_bytes = device->total_bytes;
1687 device->dev_root = root->fs_info->dev_root;
1688 device->bdev = bdev;
1689 device->in_fs_metadata = 1;
1690 device->mode = FMODE_EXCL;
1691 set_blocksize(device->bdev, 4096);
1694 sb->s_flags &= ~MS_RDONLY;
1695 ret = btrfs_prepare_sprout(root);
1699 device->fs_devices = root->fs_info->fs_devices;
1702 * we don't want write_supers to jump in here with our device
1705 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1706 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
1707 list_add(&device->dev_alloc_list,
1708 &root->fs_info->fs_devices->alloc_list);
1709 root->fs_info->fs_devices->num_devices++;
1710 root->fs_info->fs_devices->open_devices++;
1711 root->fs_info->fs_devices->rw_devices++;
1712 if (device->can_discard)
1713 root->fs_info->fs_devices->num_can_discard++;
1714 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
1716 spin_lock(&root->fs_info->free_chunk_lock);
1717 root->fs_info->free_chunk_space += device->total_bytes;
1718 spin_unlock(&root->fs_info->free_chunk_lock);
1720 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
1721 root->fs_info->fs_devices->rotating = 1;
1723 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
1724 btrfs_set_super_total_bytes(root->fs_info->super_copy,
1725 total_bytes + device->total_bytes);
1727 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy);
1728 btrfs_set_super_num_devices(root->fs_info->super_copy,
1730 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1733 ret = init_first_rw_device(trans, root, device);
1735 ret = btrfs_finish_sprout(trans, root);
1738 ret = btrfs_add_device(trans, root, device);
1742 * we've got more storage, clear any full flags on the space
1745 btrfs_clear_space_info_full(root->fs_info);
1747 unlock_chunks(root);
1748 btrfs_commit_transaction(trans, root);
1751 mutex_unlock(&uuid_mutex);
1752 up_write(&sb->s_umount);
1754 ret = btrfs_relocate_sys_chunks(root);
1758 mutex_unlock(&root->fs_info->volume_mutex);
1761 blkdev_put(bdev, FMODE_EXCL);
1763 mutex_unlock(&uuid_mutex);
1764 up_write(&sb->s_umount);
1769 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
1770 struct btrfs_device *device)
1773 struct btrfs_path *path;
1774 struct btrfs_root *root;
1775 struct btrfs_dev_item *dev_item;
1776 struct extent_buffer *leaf;
1777 struct btrfs_key key;
1779 root = device->dev_root->fs_info->chunk_root;
1781 path = btrfs_alloc_path();
1785 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1786 key.type = BTRFS_DEV_ITEM_KEY;
1787 key.offset = device->devid;
1789 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1798 leaf = path->nodes[0];
1799 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1801 btrfs_set_device_id(leaf, dev_item, device->devid);
1802 btrfs_set_device_type(leaf, dev_item, device->type);
1803 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1804 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1805 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1806 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes);
1807 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
1808 btrfs_mark_buffer_dirty(leaf);
1811 btrfs_free_path(path);
1815 static int __btrfs_grow_device(struct btrfs_trans_handle *trans,
1816 struct btrfs_device *device, u64 new_size)
1818 struct btrfs_super_block *super_copy =
1819 device->dev_root->fs_info->super_copy;
1820 u64 old_total = btrfs_super_total_bytes(super_copy);
1821 u64 diff = new_size - device->total_bytes;
1823 if (!device->writeable)
1825 if (new_size <= device->total_bytes)
1828 btrfs_set_super_total_bytes(super_copy, old_total + diff);
1829 device->fs_devices->total_rw_bytes += diff;
1831 device->total_bytes = new_size;
1832 device->disk_total_bytes = new_size;
1833 btrfs_clear_space_info_full(device->dev_root->fs_info);
1835 return btrfs_update_device(trans, device);
1838 int btrfs_grow_device(struct btrfs_trans_handle *trans,
1839 struct btrfs_device *device, u64 new_size)
1842 lock_chunks(device->dev_root);
1843 ret = __btrfs_grow_device(trans, device, new_size);
1844 unlock_chunks(device->dev_root);
1848 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
1849 struct btrfs_root *root,
1850 u64 chunk_tree, u64 chunk_objectid,
1854 struct btrfs_path *path;
1855 struct btrfs_key key;
1857 root = root->fs_info->chunk_root;
1858 path = btrfs_alloc_path();
1862 key.objectid = chunk_objectid;
1863 key.offset = chunk_offset;
1864 key.type = BTRFS_CHUNK_ITEM_KEY;
1866 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1869 ret = btrfs_del_item(trans, root, path);
1871 btrfs_free_path(path);
1875 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
1878 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
1879 struct btrfs_disk_key *disk_key;
1880 struct btrfs_chunk *chunk;
1887 struct btrfs_key key;
1889 array_size = btrfs_super_sys_array_size(super_copy);
1891 ptr = super_copy->sys_chunk_array;
1894 while (cur < array_size) {
1895 disk_key = (struct btrfs_disk_key *)ptr;
1896 btrfs_disk_key_to_cpu(&key, disk_key);
1898 len = sizeof(*disk_key);
1900 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
1901 chunk = (struct btrfs_chunk *)(ptr + len);
1902 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
1903 len += btrfs_chunk_item_size(num_stripes);
1908 if (key.objectid == chunk_objectid &&
1909 key.offset == chunk_offset) {
1910 memmove(ptr, ptr + len, array_size - (cur + len));
1912 btrfs_set_super_sys_array_size(super_copy, array_size);
1921 static int btrfs_relocate_chunk(struct btrfs_root *root,
1922 u64 chunk_tree, u64 chunk_objectid,
1925 struct extent_map_tree *em_tree;
1926 struct btrfs_root *extent_root;
1927 struct btrfs_trans_handle *trans;
1928 struct extent_map *em;
1929 struct map_lookup *map;
1933 root = root->fs_info->chunk_root;
1934 extent_root = root->fs_info->extent_root;
1935 em_tree = &root->fs_info->mapping_tree.map_tree;
1937 ret = btrfs_can_relocate(extent_root, chunk_offset);
1941 /* step one, relocate all the extents inside this chunk */
1942 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
1946 trans = btrfs_start_transaction(root, 0);
1947 BUG_ON(IS_ERR(trans));
1952 * step two, delete the device extents and the
1953 * chunk tree entries
1955 read_lock(&em_tree->lock);
1956 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
1957 read_unlock(&em_tree->lock);
1959 BUG_ON(em->start > chunk_offset ||
1960 em->start + em->len < chunk_offset);
1961 map = (struct map_lookup *)em->bdev;
1963 for (i = 0; i < map->num_stripes; i++) {
1964 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev,
1965 map->stripes[i].physical);
1968 if (map->stripes[i].dev) {
1969 ret = btrfs_update_device(trans, map->stripes[i].dev);
1973 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid,
1978 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
1980 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
1981 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
1985 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset);
1988 write_lock(&em_tree->lock);
1989 remove_extent_mapping(em_tree, em);
1990 write_unlock(&em_tree->lock);
1995 /* once for the tree */
1996 free_extent_map(em);
1998 free_extent_map(em);
2000 unlock_chunks(root);
2001 btrfs_end_transaction(trans, root);
2005 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2007 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2008 struct btrfs_path *path;
2009 struct extent_buffer *leaf;
2010 struct btrfs_chunk *chunk;
2011 struct btrfs_key key;
2012 struct btrfs_key found_key;
2013 u64 chunk_tree = chunk_root->root_key.objectid;
2015 bool retried = false;
2019 path = btrfs_alloc_path();
2024 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2025 key.offset = (u64)-1;
2026 key.type = BTRFS_CHUNK_ITEM_KEY;
2029 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2034 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2041 leaf = path->nodes[0];
2042 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2044 chunk = btrfs_item_ptr(leaf, path->slots[0],
2045 struct btrfs_chunk);
2046 chunk_type = btrfs_chunk_type(leaf, chunk);
2047 btrfs_release_path(path);
2049 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2050 ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
2059 if (found_key.offset == 0)
2061 key.offset = found_key.offset - 1;
2064 if (failed && !retried) {
2068 } else if (failed && retried) {
2073 btrfs_free_path(path);
2077 static u64 div_factor(u64 num, int factor)
2086 int btrfs_balance(struct btrfs_root *dev_root)
2089 struct list_head *devices = &dev_root->fs_info->fs_devices->devices;
2090 struct btrfs_device *device;
2093 struct btrfs_path *path;
2094 struct btrfs_key key;
2095 struct btrfs_root *chunk_root = dev_root->fs_info->chunk_root;
2096 struct btrfs_trans_handle *trans;
2097 struct btrfs_key found_key;
2099 if (dev_root->fs_info->sb->s_flags & MS_RDONLY)
2102 if (!capable(CAP_SYS_ADMIN))
2105 mutex_lock(&dev_root->fs_info->volume_mutex);
2106 dev_root = dev_root->fs_info->dev_root;
2108 /* step one make some room on all the devices */
2109 list_for_each_entry(device, devices, dev_list) {
2110 old_size = device->total_bytes;
2111 size_to_free = div_factor(old_size, 1);
2112 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
2113 if (!device->writeable ||
2114 device->total_bytes - device->bytes_used > size_to_free)
2117 ret = btrfs_shrink_device(device, old_size - size_to_free);
2122 trans = btrfs_start_transaction(dev_root, 0);
2123 BUG_ON(IS_ERR(trans));
2125 ret = btrfs_grow_device(trans, device, old_size);
2128 btrfs_end_transaction(trans, dev_root);
2131 /* step two, relocate all the chunks */
2132 path = btrfs_alloc_path();
2137 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2138 key.offset = (u64)-1;
2139 key.type = BTRFS_CHUNK_ITEM_KEY;
2142 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2147 * this shouldn't happen, it means the last relocate
2153 ret = btrfs_previous_item(chunk_root, path, 0,
2154 BTRFS_CHUNK_ITEM_KEY);
2158 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2160 if (found_key.objectid != key.objectid)
2163 /* chunk zero is special */
2164 if (found_key.offset == 0)
2167 btrfs_release_path(path);
2168 ret = btrfs_relocate_chunk(chunk_root,
2169 chunk_root->root_key.objectid,
2172 if (ret && ret != -ENOSPC)
2174 key.offset = found_key.offset - 1;
2178 btrfs_free_path(path);
2179 mutex_unlock(&dev_root->fs_info->volume_mutex);
2184 * shrinking a device means finding all of the device extents past
2185 * the new size, and then following the back refs to the chunks.
2186 * The chunk relocation code actually frees the device extent
2188 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
2190 struct btrfs_trans_handle *trans;
2191 struct btrfs_root *root = device->dev_root;
2192 struct btrfs_dev_extent *dev_extent = NULL;
2193 struct btrfs_path *path;
2201 bool retried = false;
2202 struct extent_buffer *l;
2203 struct btrfs_key key;
2204 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2205 u64 old_total = btrfs_super_total_bytes(super_copy);
2206 u64 old_size = device->total_bytes;
2207 u64 diff = device->total_bytes - new_size;
2209 if (new_size >= device->total_bytes)
2212 path = btrfs_alloc_path();
2220 device->total_bytes = new_size;
2221 if (device->writeable) {
2222 device->fs_devices->total_rw_bytes -= diff;
2223 spin_lock(&root->fs_info->free_chunk_lock);
2224 root->fs_info->free_chunk_space -= diff;
2225 spin_unlock(&root->fs_info->free_chunk_lock);
2227 unlock_chunks(root);
2230 key.objectid = device->devid;
2231 key.offset = (u64)-1;
2232 key.type = BTRFS_DEV_EXTENT_KEY;
2235 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2239 ret = btrfs_previous_item(root, path, 0, key.type);
2244 btrfs_release_path(path);
2249 slot = path->slots[0];
2250 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
2252 if (key.objectid != device->devid) {
2253 btrfs_release_path(path);
2257 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
2258 length = btrfs_dev_extent_length(l, dev_extent);
2260 if (key.offset + length <= new_size) {
2261 btrfs_release_path(path);
2265 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
2266 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
2267 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
2268 btrfs_release_path(path);
2270 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
2272 if (ret && ret != -ENOSPC)
2279 if (failed && !retried) {
2283 } else if (failed && retried) {
2287 device->total_bytes = old_size;
2288 if (device->writeable)
2289 device->fs_devices->total_rw_bytes += diff;
2290 spin_lock(&root->fs_info->free_chunk_lock);
2291 root->fs_info->free_chunk_space += diff;
2292 spin_unlock(&root->fs_info->free_chunk_lock);
2293 unlock_chunks(root);
2297 /* Shrinking succeeded, else we would be at "done". */
2298 trans = btrfs_start_transaction(root, 0);
2299 if (IS_ERR(trans)) {
2300 ret = PTR_ERR(trans);
2306 device->disk_total_bytes = new_size;
2307 /* Now btrfs_update_device() will change the on-disk size. */
2308 ret = btrfs_update_device(trans, device);
2310 unlock_chunks(root);
2311 btrfs_end_transaction(trans, root);
2314 WARN_ON(diff > old_total);
2315 btrfs_set_super_total_bytes(super_copy, old_total - diff);
2316 unlock_chunks(root);
2317 btrfs_end_transaction(trans, root);
2319 btrfs_free_path(path);
2323 static int btrfs_add_system_chunk(struct btrfs_root *root,
2324 struct btrfs_key *key,
2325 struct btrfs_chunk *chunk, int item_size)
2327 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2328 struct btrfs_disk_key disk_key;
2332 array_size = btrfs_super_sys_array_size(super_copy);
2333 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
2336 ptr = super_copy->sys_chunk_array + array_size;
2337 btrfs_cpu_key_to_disk(&disk_key, key);
2338 memcpy(ptr, &disk_key, sizeof(disk_key));
2339 ptr += sizeof(disk_key);
2340 memcpy(ptr, chunk, item_size);
2341 item_size += sizeof(disk_key);
2342 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
2347 * sort the devices in descending order by max_avail, total_avail
2349 static int btrfs_cmp_device_info(const void *a, const void *b)
2351 const struct btrfs_device_info *di_a = a;
2352 const struct btrfs_device_info *di_b = b;
2354 if (di_a->max_avail > di_b->max_avail)
2356 if (di_a->max_avail < di_b->max_avail)
2358 if (di_a->total_avail > di_b->total_avail)
2360 if (di_a->total_avail < di_b->total_avail)
2365 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
2366 struct btrfs_root *extent_root,
2367 struct map_lookup **map_ret,
2368 u64 *num_bytes_out, u64 *stripe_size_out,
2369 u64 start, u64 type)
2371 struct btrfs_fs_info *info = extent_root->fs_info;
2372 struct btrfs_fs_devices *fs_devices = info->fs_devices;
2373 struct list_head *cur;
2374 struct map_lookup *map = NULL;
2375 struct extent_map_tree *em_tree;
2376 struct extent_map *em;
2377 struct btrfs_device_info *devices_info = NULL;
2379 int num_stripes; /* total number of stripes to allocate */
2380 int sub_stripes; /* sub_stripes info for map */
2381 int dev_stripes; /* stripes per dev */
2382 int devs_max; /* max devs to use */
2383 int devs_min; /* min devs needed */
2384 int devs_increment; /* ndevs has to be a multiple of this */
2385 int ncopies; /* how many copies to data has */
2387 u64 max_stripe_size;
2395 if ((type & BTRFS_BLOCK_GROUP_RAID1) &&
2396 (type & BTRFS_BLOCK_GROUP_DUP)) {
2398 type &= ~BTRFS_BLOCK_GROUP_DUP;
2401 if (list_empty(&fs_devices->alloc_list))
2408 devs_max = 0; /* 0 == as many as possible */
2412 * define the properties of each RAID type.
2413 * FIXME: move this to a global table and use it in all RAID
2416 if (type & (BTRFS_BLOCK_GROUP_DUP)) {
2420 } else if (type & (BTRFS_BLOCK_GROUP_RAID0)) {
2422 } else if (type & (BTRFS_BLOCK_GROUP_RAID1)) {
2427 } else if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
2436 if (type & BTRFS_BLOCK_GROUP_DATA) {
2437 max_stripe_size = 1024 * 1024 * 1024;
2438 max_chunk_size = 10 * max_stripe_size;
2439 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
2440 max_stripe_size = 256 * 1024 * 1024;
2441 max_chunk_size = max_stripe_size;
2442 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
2443 max_stripe_size = 8 * 1024 * 1024;
2444 max_chunk_size = 2 * max_stripe_size;
2446 printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n",
2451 /* we don't want a chunk larger than 10% of writeable space */
2452 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
2455 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices,
2460 cur = fs_devices->alloc_list.next;
2463 * in the first pass through the devices list, we gather information
2464 * about the available holes on each device.
2467 while (cur != &fs_devices->alloc_list) {
2468 struct btrfs_device *device;
2472 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
2476 if (!device->writeable) {
2478 "btrfs: read-only device in alloc_list\n");
2483 if (!device->in_fs_metadata)
2486 if (device->total_bytes > device->bytes_used)
2487 total_avail = device->total_bytes - device->bytes_used;
2491 /* If there is no space on this device, skip it. */
2492 if (total_avail == 0)
2495 ret = find_free_dev_extent(device,
2496 max_stripe_size * dev_stripes,
2497 &dev_offset, &max_avail);
2498 if (ret && ret != -ENOSPC)
2502 max_avail = max_stripe_size * dev_stripes;
2504 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
2507 devices_info[ndevs].dev_offset = dev_offset;
2508 devices_info[ndevs].max_avail = max_avail;
2509 devices_info[ndevs].total_avail = total_avail;
2510 devices_info[ndevs].dev = device;
2515 * now sort the devices by hole size / available space
2517 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
2518 btrfs_cmp_device_info, NULL);
2520 /* round down to number of usable stripes */
2521 ndevs -= ndevs % devs_increment;
2523 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
2528 if (devs_max && ndevs > devs_max)
2531 * the primary goal is to maximize the number of stripes, so use as many
2532 * devices as possible, even if the stripes are not maximum sized.
2534 stripe_size = devices_info[ndevs-1].max_avail;
2535 num_stripes = ndevs * dev_stripes;
2537 if (stripe_size * num_stripes > max_chunk_size * ncopies) {
2538 stripe_size = max_chunk_size * ncopies;
2539 do_div(stripe_size, num_stripes);
2542 do_div(stripe_size, dev_stripes);
2543 do_div(stripe_size, BTRFS_STRIPE_LEN);
2544 stripe_size *= BTRFS_STRIPE_LEN;
2546 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
2551 map->num_stripes = num_stripes;
2553 for (i = 0; i < ndevs; ++i) {
2554 for (j = 0; j < dev_stripes; ++j) {
2555 int s = i * dev_stripes + j;
2556 map->stripes[s].dev = devices_info[i].dev;
2557 map->stripes[s].physical = devices_info[i].dev_offset +
2561 map->sector_size = extent_root->sectorsize;
2562 map->stripe_len = BTRFS_STRIPE_LEN;
2563 map->io_align = BTRFS_STRIPE_LEN;
2564 map->io_width = BTRFS_STRIPE_LEN;
2566 map->sub_stripes = sub_stripes;
2569 num_bytes = stripe_size * (num_stripes / ncopies);
2571 *stripe_size_out = stripe_size;
2572 *num_bytes_out = num_bytes;
2574 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
2576 em = alloc_extent_map();
2581 em->bdev = (struct block_device *)map;
2583 em->len = num_bytes;
2584 em->block_start = 0;
2585 em->block_len = em->len;
2587 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
2588 write_lock(&em_tree->lock);
2589 ret = add_extent_mapping(em_tree, em);
2590 write_unlock(&em_tree->lock);
2592 free_extent_map(em);
2594 ret = btrfs_make_block_group(trans, extent_root, 0, type,
2595 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2599 for (i = 0; i < map->num_stripes; ++i) {
2600 struct btrfs_device *device;
2603 device = map->stripes[i].dev;
2604 dev_offset = map->stripes[i].physical;
2606 ret = btrfs_alloc_dev_extent(trans, device,
2607 info->chunk_root->root_key.objectid,
2608 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2609 start, dev_offset, stripe_size);
2613 kfree(devices_info);
2618 kfree(devices_info);
2622 static int __finish_chunk_alloc(struct btrfs_trans_handle *trans,
2623 struct btrfs_root *extent_root,
2624 struct map_lookup *map, u64 chunk_offset,
2625 u64 chunk_size, u64 stripe_size)
2628 struct btrfs_key key;
2629 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
2630 struct btrfs_device *device;
2631 struct btrfs_chunk *chunk;
2632 struct btrfs_stripe *stripe;
2633 size_t item_size = btrfs_chunk_item_size(map->num_stripes);
2637 chunk = kzalloc(item_size, GFP_NOFS);
2642 while (index < map->num_stripes) {
2643 device = map->stripes[index].dev;
2644 device->bytes_used += stripe_size;
2645 ret = btrfs_update_device(trans, device);
2650 spin_lock(&extent_root->fs_info->free_chunk_lock);
2651 extent_root->fs_info->free_chunk_space -= (stripe_size *
2653 spin_unlock(&extent_root->fs_info->free_chunk_lock);
2656 stripe = &chunk->stripe;
2657 while (index < map->num_stripes) {
2658 device = map->stripes[index].dev;
2659 dev_offset = map->stripes[index].physical;
2661 btrfs_set_stack_stripe_devid(stripe, device->devid);
2662 btrfs_set_stack_stripe_offset(stripe, dev_offset);
2663 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
2668 btrfs_set_stack_chunk_length(chunk, chunk_size);
2669 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
2670 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
2671 btrfs_set_stack_chunk_type(chunk, map->type);
2672 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
2673 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
2674 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
2675 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
2676 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
2678 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2679 key.type = BTRFS_CHUNK_ITEM_KEY;
2680 key.offset = chunk_offset;
2682 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
2685 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2686 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
2696 * Chunk allocation falls into two parts. The first part does works
2697 * that make the new allocated chunk useable, but not do any operation
2698 * that modifies the chunk tree. The second part does the works that
2699 * require modifying the chunk tree. This division is important for the
2700 * bootstrap process of adding storage to a seed btrfs.
2702 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
2703 struct btrfs_root *extent_root, u64 type)
2708 struct map_lookup *map;
2709 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
2712 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2717 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
2718 &stripe_size, chunk_offset, type);
2722 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
2723 chunk_size, stripe_size);
2728 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
2729 struct btrfs_root *root,
2730 struct btrfs_device *device)
2733 u64 sys_chunk_offset;
2737 u64 sys_stripe_size;
2739 struct map_lookup *map;
2740 struct map_lookup *sys_map;
2741 struct btrfs_fs_info *fs_info = root->fs_info;
2742 struct btrfs_root *extent_root = fs_info->extent_root;
2745 ret = find_next_chunk(fs_info->chunk_root,
2746 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset);
2750 alloc_profile = BTRFS_BLOCK_GROUP_METADATA |
2751 (fs_info->metadata_alloc_profile &
2752 fs_info->avail_metadata_alloc_bits);
2753 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
2755 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
2756 &stripe_size, chunk_offset, alloc_profile);
2759 sys_chunk_offset = chunk_offset + chunk_size;
2761 alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM |
2762 (fs_info->system_alloc_profile &
2763 fs_info->avail_system_alloc_bits);
2764 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
2766 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map,
2767 &sys_chunk_size, &sys_stripe_size,
2768 sys_chunk_offset, alloc_profile);
2771 ret = btrfs_add_device(trans, fs_info->chunk_root, device);
2775 * Modifying chunk tree needs allocating new blocks from both
2776 * system block group and metadata block group. So we only can
2777 * do operations require modifying the chunk tree after both
2778 * block groups were created.
2780 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
2781 chunk_size, stripe_size);
2784 ret = __finish_chunk_alloc(trans, extent_root, sys_map,
2785 sys_chunk_offset, sys_chunk_size,
2791 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
2793 struct extent_map *em;
2794 struct map_lookup *map;
2795 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
2799 read_lock(&map_tree->map_tree.lock);
2800 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
2801 read_unlock(&map_tree->map_tree.lock);
2805 if (btrfs_test_opt(root, DEGRADED)) {
2806 free_extent_map(em);
2810 map = (struct map_lookup *)em->bdev;
2811 for (i = 0; i < map->num_stripes; i++) {
2812 if (!map->stripes[i].dev->writeable) {
2817 free_extent_map(em);
2821 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
2823 extent_map_tree_init(&tree->map_tree);
2826 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
2828 struct extent_map *em;
2831 write_lock(&tree->map_tree.lock);
2832 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
2834 remove_extent_mapping(&tree->map_tree, em);
2835 write_unlock(&tree->map_tree.lock);
2840 free_extent_map(em);
2841 /* once for the tree */
2842 free_extent_map(em);
2846 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len)
2848 struct extent_map *em;
2849 struct map_lookup *map;
2850 struct extent_map_tree *em_tree = &map_tree->map_tree;
2853 read_lock(&em_tree->lock);
2854 em = lookup_extent_mapping(em_tree, logical, len);
2855 read_unlock(&em_tree->lock);
2858 BUG_ON(em->start > logical || em->start + em->len < logical);
2859 map = (struct map_lookup *)em->bdev;
2860 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
2861 ret = map->num_stripes;
2862 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
2863 ret = map->sub_stripes;
2866 free_extent_map(em);
2870 static int find_live_mirror(struct map_lookup *map, int first, int num,
2874 if (map->stripes[optimal].dev->bdev)
2876 for (i = first; i < first + num; i++) {
2877 if (map->stripes[i].dev->bdev)
2880 /* we couldn't find one that doesn't fail. Just return something
2881 * and the io error handling code will clean up eventually
2886 static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
2887 u64 logical, u64 *length,
2888 struct btrfs_bio **bbio_ret,
2891 struct extent_map *em;
2892 struct map_lookup *map;
2893 struct extent_map_tree *em_tree = &map_tree->map_tree;
2896 u64 stripe_end_offset;
2900 int stripes_allocated = 8;
2901 int stripes_required = 1;
2906 struct btrfs_bio *bbio = NULL;
2908 if (bbio_ret && !(rw & (REQ_WRITE | REQ_DISCARD)))
2909 stripes_allocated = 1;
2912 bbio = kzalloc(btrfs_bio_size(stripes_allocated),
2917 atomic_set(&bbio->error, 0);
2920 read_lock(&em_tree->lock);
2921 em = lookup_extent_mapping(em_tree, logical, *length);
2922 read_unlock(&em_tree->lock);
2925 printk(KERN_CRIT "unable to find logical %llu len %llu\n",
2926 (unsigned long long)logical,
2927 (unsigned long long)*length);
2931 BUG_ON(em->start > logical || em->start + em->len < logical);
2932 map = (struct map_lookup *)em->bdev;
2933 offset = logical - em->start;
2935 if (mirror_num > map->num_stripes)
2938 /* if our btrfs_bio struct is too small, back off and try again */
2939 if (rw & REQ_WRITE) {
2940 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
2941 BTRFS_BLOCK_GROUP_DUP)) {
2942 stripes_required = map->num_stripes;
2944 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2945 stripes_required = map->sub_stripes;
2949 if (rw & REQ_DISCARD) {
2950 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
2951 BTRFS_BLOCK_GROUP_RAID1 |
2952 BTRFS_BLOCK_GROUP_DUP |
2953 BTRFS_BLOCK_GROUP_RAID10)) {
2954 stripes_required = map->num_stripes;
2957 if (bbio_ret && (rw & (REQ_WRITE | REQ_DISCARD)) &&
2958 stripes_allocated < stripes_required) {
2959 stripes_allocated = map->num_stripes;
2960 free_extent_map(em);
2966 * stripe_nr counts the total number of stripes we have to stride
2967 * to get to this block
2969 do_div(stripe_nr, map->stripe_len);
2971 stripe_offset = stripe_nr * map->stripe_len;
2972 BUG_ON(offset < stripe_offset);
2974 /* stripe_offset is the offset of this block in its stripe*/
2975 stripe_offset = offset - stripe_offset;
2977 if (rw & REQ_DISCARD)
2978 *length = min_t(u64, em->len - offset, *length);
2979 else if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
2980 BTRFS_BLOCK_GROUP_RAID1 |
2981 BTRFS_BLOCK_GROUP_RAID10 |
2982 BTRFS_BLOCK_GROUP_DUP)) {
2983 /* we limit the length of each bio to what fits in a stripe */
2984 *length = min_t(u64, em->len - offset,
2985 map->stripe_len - stripe_offset);
2987 *length = em->len - offset;
2995 stripe_nr_orig = stripe_nr;
2996 stripe_nr_end = (offset + *length + map->stripe_len - 1) &
2997 (~(map->stripe_len - 1));
2998 do_div(stripe_nr_end, map->stripe_len);
2999 stripe_end_offset = stripe_nr_end * map->stripe_len -
3001 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
3002 if (rw & REQ_DISCARD)
3003 num_stripes = min_t(u64, map->num_stripes,
3004 stripe_nr_end - stripe_nr_orig);
3005 stripe_index = do_div(stripe_nr, map->num_stripes);
3006 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
3007 if (rw & (REQ_WRITE | REQ_DISCARD))
3008 num_stripes = map->num_stripes;
3009 else if (mirror_num)
3010 stripe_index = mirror_num - 1;
3012 stripe_index = find_live_mirror(map, 0,
3014 current->pid % map->num_stripes);
3015 mirror_num = stripe_index + 1;
3018 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
3019 if (rw & (REQ_WRITE | REQ_DISCARD)) {
3020 num_stripes = map->num_stripes;
3021 } else if (mirror_num) {
3022 stripe_index = mirror_num - 1;
3027 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
3028 int factor = map->num_stripes / map->sub_stripes;
3030 stripe_index = do_div(stripe_nr, factor);
3031 stripe_index *= map->sub_stripes;
3034 num_stripes = map->sub_stripes;
3035 else if (rw & REQ_DISCARD)
3036 num_stripes = min_t(u64, map->sub_stripes *
3037 (stripe_nr_end - stripe_nr_orig),
3039 else if (mirror_num)
3040 stripe_index += mirror_num - 1;
3042 stripe_index = find_live_mirror(map, stripe_index,
3043 map->sub_stripes, stripe_index +
3044 current->pid % map->sub_stripes);
3045 mirror_num = stripe_index + 1;
3049 * after this do_div call, stripe_nr is the number of stripes
3050 * on this device we have to walk to find the data, and
3051 * stripe_index is the number of our device in the stripe array
3053 stripe_index = do_div(stripe_nr, map->num_stripes);
3054 mirror_num = stripe_index + 1;
3056 BUG_ON(stripe_index >= map->num_stripes);
3058 if (rw & REQ_DISCARD) {
3059 for (i = 0; i < num_stripes; i++) {
3060 bbio->stripes[i].physical =
3061 map->stripes[stripe_index].physical +
3062 stripe_offset + stripe_nr * map->stripe_len;
3063 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
3065 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
3067 u32 last_stripe = 0;
3070 div_u64_rem(stripe_nr_end - 1,
3074 for (j = 0; j < map->num_stripes; j++) {
3077 div_u64_rem(stripe_nr_end - 1 - j,
3078 map->num_stripes, &test);
3079 if (test == stripe_index)
3082 stripes = stripe_nr_end - 1 - j;
3083 do_div(stripes, map->num_stripes);
3084 bbio->stripes[i].length = map->stripe_len *
3085 (stripes - stripe_nr + 1);
3088 bbio->stripes[i].length -=
3092 if (stripe_index == last_stripe)
3093 bbio->stripes[i].length -=
3095 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
3098 int factor = map->num_stripes /
3100 u32 last_stripe = 0;
3102 div_u64_rem(stripe_nr_end - 1,
3103 factor, &last_stripe);
3104 last_stripe *= map->sub_stripes;
3106 for (j = 0; j < factor; j++) {
3109 div_u64_rem(stripe_nr_end - 1 - j,
3113 stripe_index / map->sub_stripes)
3116 stripes = stripe_nr_end - 1 - j;
3117 do_div(stripes, factor);
3118 bbio->stripes[i].length = map->stripe_len *
3119 (stripes - stripe_nr + 1);
3121 if (i < map->sub_stripes) {
3122 bbio->stripes[i].length -=
3124 if (i == map->sub_stripes - 1)
3127 if (stripe_index >= last_stripe &&
3128 stripe_index <= (last_stripe +
3129 map->sub_stripes - 1)) {
3130 bbio->stripes[i].length -=
3134 bbio->stripes[i].length = *length;
3137 if (stripe_index == map->num_stripes) {
3138 /* This could only happen for RAID0/10 */
3144 for (i = 0; i < num_stripes; i++) {
3145 bbio->stripes[i].physical =
3146 map->stripes[stripe_index].physical +
3148 stripe_nr * map->stripe_len;
3149 bbio->stripes[i].dev =
3150 map->stripes[stripe_index].dev;
3156 bbio->num_stripes = num_stripes;
3157 bbio->max_errors = max_errors;
3158 bbio->mirror_num = mirror_num;
3161 free_extent_map(em);
3165 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
3166 u64 logical, u64 *length,
3167 struct btrfs_bio **bbio_ret, int mirror_num)
3169 return __btrfs_map_block(map_tree, rw, logical, length, bbio_ret,
3173 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
3174 u64 chunk_start, u64 physical, u64 devid,
3175 u64 **logical, int *naddrs, int *stripe_len)
3177 struct extent_map_tree *em_tree = &map_tree->map_tree;
3178 struct extent_map *em;
3179 struct map_lookup *map;
3186 read_lock(&em_tree->lock);
3187 em = lookup_extent_mapping(em_tree, chunk_start, 1);
3188 read_unlock(&em_tree->lock);
3190 BUG_ON(!em || em->start != chunk_start);
3191 map = (struct map_lookup *)em->bdev;
3194 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
3195 do_div(length, map->num_stripes / map->sub_stripes);
3196 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
3197 do_div(length, map->num_stripes);
3199 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
3202 for (i = 0; i < map->num_stripes; i++) {
3203 if (devid && map->stripes[i].dev->devid != devid)
3205 if (map->stripes[i].physical > physical ||
3206 map->stripes[i].physical + length <= physical)
3209 stripe_nr = physical - map->stripes[i].physical;
3210 do_div(stripe_nr, map->stripe_len);
3212 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
3213 stripe_nr = stripe_nr * map->num_stripes + i;
3214 do_div(stripe_nr, map->sub_stripes);
3215 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
3216 stripe_nr = stripe_nr * map->num_stripes + i;
3218 bytenr = chunk_start + stripe_nr * map->stripe_len;
3219 WARN_ON(nr >= map->num_stripes);
3220 for (j = 0; j < nr; j++) {
3221 if (buf[j] == bytenr)
3225 WARN_ON(nr >= map->num_stripes);
3232 *stripe_len = map->stripe_len;
3234 free_extent_map(em);
3238 static void btrfs_end_bio(struct bio *bio, int err)
3240 struct btrfs_bio *bbio = bio->bi_private;
3241 int is_orig_bio = 0;
3244 atomic_inc(&bbio->error);
3246 if (bio == bbio->orig_bio)
3249 if (atomic_dec_and_test(&bbio->stripes_pending)) {
3252 bio = bbio->orig_bio;
3254 bio->bi_private = bbio->private;
3255 bio->bi_end_io = bbio->end_io;
3256 bio->bi_bdev = (struct block_device *)
3257 (unsigned long)bbio->mirror_num;
3258 /* only send an error to the higher layers if it is
3259 * beyond the tolerance of the multi-bio
3261 if (atomic_read(&bbio->error) > bbio->max_errors) {
3265 * this bio is actually up to date, we didn't
3266 * go over the max number of errors
3268 set_bit(BIO_UPTODATE, &bio->bi_flags);
3273 bio_endio(bio, err);
3274 } else if (!is_orig_bio) {
3279 struct async_sched {
3282 struct btrfs_fs_info *info;
3283 struct btrfs_work work;
3287 * see run_scheduled_bios for a description of why bios are collected for
3290 * This will add one bio to the pending list for a device and make sure
3291 * the work struct is scheduled.
3293 static noinline int schedule_bio(struct btrfs_root *root,
3294 struct btrfs_device *device,
3295 int rw, struct bio *bio)
3297 int should_queue = 1;
3298 struct btrfs_pending_bios *pending_bios;
3300 /* don't bother with additional async steps for reads, right now */
3301 if (!(rw & REQ_WRITE)) {
3303 submit_bio(rw, bio);
3309 * nr_async_bios allows us to reliably return congestion to the
3310 * higher layers. Otherwise, the async bio makes it appear we have
3311 * made progress against dirty pages when we've really just put it
3312 * on a queue for later
3314 atomic_inc(&root->fs_info->nr_async_bios);
3315 WARN_ON(bio->bi_next);
3316 bio->bi_next = NULL;
3319 spin_lock(&device->io_lock);
3320 if (bio->bi_rw & REQ_SYNC)
3321 pending_bios = &device->pending_sync_bios;
3323 pending_bios = &device->pending_bios;
3325 if (pending_bios->tail)
3326 pending_bios->tail->bi_next = bio;
3328 pending_bios->tail = bio;
3329 if (!pending_bios->head)
3330 pending_bios->head = bio;
3331 if (device->running_pending)
3334 spin_unlock(&device->io_lock);
3337 btrfs_queue_worker(&root->fs_info->submit_workers,
3342 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
3343 int mirror_num, int async_submit)
3345 struct btrfs_mapping_tree *map_tree;
3346 struct btrfs_device *dev;
3347 struct bio *first_bio = bio;
3348 u64 logical = (u64)bio->bi_sector << 9;
3354 struct btrfs_bio *bbio = NULL;
3356 length = bio->bi_size;
3357 map_tree = &root->fs_info->mapping_tree;
3358 map_length = length;
3360 ret = btrfs_map_block(map_tree, rw, logical, &map_length, &bbio,
3364 total_devs = bbio->num_stripes;
3365 if (map_length < length) {
3366 printk(KERN_CRIT "mapping failed logical %llu bio len %llu "
3367 "len %llu\n", (unsigned long long)logical,
3368 (unsigned long long)length,
3369 (unsigned long long)map_length);
3373 bbio->orig_bio = first_bio;
3374 bbio->private = first_bio->bi_private;
3375 bbio->end_io = first_bio->bi_end_io;
3376 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
3378 while (dev_nr < total_devs) {
3379 if (dev_nr < total_devs - 1) {
3380 bio = bio_clone(first_bio, GFP_NOFS);
3385 bio->bi_private = bbio;
3386 bio->bi_end_io = btrfs_end_bio;
3387 bio->bi_sector = bbio->stripes[dev_nr].physical >> 9;
3388 dev = bbio->stripes[dev_nr].dev;
3389 if (dev && dev->bdev && (rw != WRITE || dev->writeable)) {
3390 pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu "
3391 "(%s id %llu), size=%u\n", rw,
3392 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev,
3393 dev->name, dev->devid, bio->bi_size);
3394 bio->bi_bdev = dev->bdev;
3396 schedule_bio(root, dev, rw, bio);
3398 submit_bio(rw, bio);
3400 bio->bi_bdev = root->fs_info->fs_devices->latest_bdev;
3401 bio->bi_sector = logical >> 9;
3402 bio_endio(bio, -EIO);
3409 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
3412 struct btrfs_device *device;
3413 struct btrfs_fs_devices *cur_devices;
3415 cur_devices = root->fs_info->fs_devices;
3416 while (cur_devices) {
3418 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
3419 device = __find_device(&cur_devices->devices,
3424 cur_devices = cur_devices->seed;
3429 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
3430 u64 devid, u8 *dev_uuid)
3432 struct btrfs_device *device;
3433 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
3435 device = kzalloc(sizeof(*device), GFP_NOFS);
3438 list_add(&device->dev_list,
3439 &fs_devices->devices);
3440 device->dev_root = root->fs_info->dev_root;
3441 device->devid = devid;
3442 device->work.func = pending_bios_fn;
3443 device->fs_devices = fs_devices;
3444 device->missing = 1;
3445 fs_devices->num_devices++;
3446 fs_devices->missing_devices++;
3447 spin_lock_init(&device->io_lock);
3448 INIT_LIST_HEAD(&device->dev_alloc_list);
3449 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE);
3453 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
3454 struct extent_buffer *leaf,
3455 struct btrfs_chunk *chunk)
3457 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
3458 struct map_lookup *map;
3459 struct extent_map *em;
3463 u8 uuid[BTRFS_UUID_SIZE];
3468 logical = key->offset;
3469 length = btrfs_chunk_length(leaf, chunk);
3471 read_lock(&map_tree->map_tree.lock);
3472 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
3473 read_unlock(&map_tree->map_tree.lock);
3475 /* already mapped? */
3476 if (em && em->start <= logical && em->start + em->len > logical) {
3477 free_extent_map(em);
3480 free_extent_map(em);
3483 em = alloc_extent_map();
3486 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3487 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
3489 free_extent_map(em);
3493 em->bdev = (struct block_device *)map;
3494 em->start = logical;
3496 em->block_start = 0;
3497 em->block_len = em->len;
3499 map->num_stripes = num_stripes;
3500 map->io_width = btrfs_chunk_io_width(leaf, chunk);
3501 map->io_align = btrfs_chunk_io_align(leaf, chunk);
3502 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
3503 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
3504 map->type = btrfs_chunk_type(leaf, chunk);
3505 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
3506 for (i = 0; i < num_stripes; i++) {
3507 map->stripes[i].physical =
3508 btrfs_stripe_offset_nr(leaf, chunk, i);
3509 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
3510 read_extent_buffer(leaf, uuid, (unsigned long)
3511 btrfs_stripe_dev_uuid_nr(chunk, i),
3513 map->stripes[i].dev = btrfs_find_device(root, devid, uuid,
3515 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
3517 free_extent_map(em);
3520 if (!map->stripes[i].dev) {
3521 map->stripes[i].dev =
3522 add_missing_dev(root, devid, uuid);
3523 if (!map->stripes[i].dev) {
3525 free_extent_map(em);
3529 map->stripes[i].dev->in_fs_metadata = 1;
3532 write_lock(&map_tree->map_tree.lock);
3533 ret = add_extent_mapping(&map_tree->map_tree, em);
3534 write_unlock(&map_tree->map_tree.lock);
3536 free_extent_map(em);
3541 static int fill_device_from_item(struct extent_buffer *leaf,
3542 struct btrfs_dev_item *dev_item,
3543 struct btrfs_device *device)
3547 device->devid = btrfs_device_id(leaf, dev_item);
3548 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
3549 device->total_bytes = device->disk_total_bytes;
3550 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
3551 device->type = btrfs_device_type(leaf, dev_item);
3552 device->io_align = btrfs_device_io_align(leaf, dev_item);
3553 device->io_width = btrfs_device_io_width(leaf, dev_item);
3554 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
3556 ptr = (unsigned long)btrfs_device_uuid(dev_item);
3557 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
3562 static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
3564 struct btrfs_fs_devices *fs_devices;
3567 mutex_lock(&uuid_mutex);
3569 fs_devices = root->fs_info->fs_devices->seed;
3570 while (fs_devices) {
3571 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
3575 fs_devices = fs_devices->seed;
3578 fs_devices = find_fsid(fsid);
3584 fs_devices = clone_fs_devices(fs_devices);
3585 if (IS_ERR(fs_devices)) {
3586 ret = PTR_ERR(fs_devices);
3590 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
3591 root->fs_info->bdev_holder);
3595 if (!fs_devices->seeding) {
3596 __btrfs_close_devices(fs_devices);
3597 free_fs_devices(fs_devices);
3602 fs_devices->seed = root->fs_info->fs_devices->seed;
3603 root->fs_info->fs_devices->seed = fs_devices;
3605 mutex_unlock(&uuid_mutex);
3609 static int read_one_dev(struct btrfs_root *root,
3610 struct extent_buffer *leaf,
3611 struct btrfs_dev_item *dev_item)
3613 struct btrfs_device *device;
3616 u8 fs_uuid[BTRFS_UUID_SIZE];
3617 u8 dev_uuid[BTRFS_UUID_SIZE];
3619 devid = btrfs_device_id(leaf, dev_item);
3620 read_extent_buffer(leaf, dev_uuid,
3621 (unsigned long)btrfs_device_uuid(dev_item),
3623 read_extent_buffer(leaf, fs_uuid,
3624 (unsigned long)btrfs_device_fsid(dev_item),
3627 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
3628 ret = open_seed_devices(root, fs_uuid);
3629 if (ret && !btrfs_test_opt(root, DEGRADED))
3633 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
3634 if (!device || !device->bdev) {
3635 if (!btrfs_test_opt(root, DEGRADED))
3639 printk(KERN_WARNING "warning devid %llu missing\n",
3640 (unsigned long long)devid);
3641 device = add_missing_dev(root, devid, dev_uuid);
3644 } else if (!device->missing) {
3646 * this happens when a device that was properly setup
3647 * in the device info lists suddenly goes bad.
3648 * device->bdev is NULL, and so we have to set
3649 * device->missing to one here
3651 root->fs_info->fs_devices->missing_devices++;
3652 device->missing = 1;
3656 if (device->fs_devices != root->fs_info->fs_devices) {
3657 BUG_ON(device->writeable);
3658 if (device->generation !=
3659 btrfs_device_generation(leaf, dev_item))
3663 fill_device_from_item(leaf, dev_item, device);
3664 device->dev_root = root->fs_info->dev_root;
3665 device->in_fs_metadata = 1;
3666 if (device->writeable) {
3667 device->fs_devices->total_rw_bytes += device->total_bytes;
3668 spin_lock(&root->fs_info->free_chunk_lock);
3669 root->fs_info->free_chunk_space += device->total_bytes -
3671 spin_unlock(&root->fs_info->free_chunk_lock);
3677 int btrfs_read_sys_array(struct btrfs_root *root)
3679 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
3680 struct extent_buffer *sb;
3681 struct btrfs_disk_key *disk_key;
3682 struct btrfs_chunk *chunk;
3684 unsigned long sb_ptr;
3690 struct btrfs_key key;
3692 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
3693 BTRFS_SUPER_INFO_SIZE);
3696 btrfs_set_buffer_uptodate(sb);
3697 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
3699 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
3700 array_size = btrfs_super_sys_array_size(super_copy);
3702 ptr = super_copy->sys_chunk_array;
3703 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
3706 while (cur < array_size) {
3707 disk_key = (struct btrfs_disk_key *)ptr;
3708 btrfs_disk_key_to_cpu(&key, disk_key);
3710 len = sizeof(*disk_key); ptr += len;
3714 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
3715 chunk = (struct btrfs_chunk *)sb_ptr;
3716 ret = read_one_chunk(root, &key, sb, chunk);
3719 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
3720 len = btrfs_chunk_item_size(num_stripes);
3729 free_extent_buffer(sb);
3733 int btrfs_read_chunk_tree(struct btrfs_root *root)
3735 struct btrfs_path *path;
3736 struct extent_buffer *leaf;
3737 struct btrfs_key key;
3738 struct btrfs_key found_key;
3742 root = root->fs_info->chunk_root;
3744 path = btrfs_alloc_path();
3748 /* first we search for all of the device items, and then we
3749 * read in all of the chunk items. This way we can create chunk
3750 * mappings that reference all of the devices that are afound
3752 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
3756 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3760 leaf = path->nodes[0];
3761 slot = path->slots[0];
3762 if (slot >= btrfs_header_nritems(leaf)) {
3763 ret = btrfs_next_leaf(root, path);
3770 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3771 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
3772 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
3774 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
3775 struct btrfs_dev_item *dev_item;
3776 dev_item = btrfs_item_ptr(leaf, slot,
3777 struct btrfs_dev_item);
3778 ret = read_one_dev(root, leaf, dev_item);
3782 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
3783 struct btrfs_chunk *chunk;
3784 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3785 ret = read_one_chunk(root, &found_key, leaf, chunk);
3791 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
3793 btrfs_release_path(path);
3798 btrfs_free_path(path);